Turbos have turbo lag, turbos drop power before redline, turbos are less reliable and often more expensive than NA engines, and most importantly to me, turbos make the car's exhaust sound worse.

Given enough time, money, and resources, I'm sure the M division will find a way to make turbo technology work for what we want.

Reducing turbo lag has come a long way already. I think the engineers just need to focus on further smoothing out power delivery through the entire RPM range and of course working on building the engine to tolerate full boost at 8k+ RPM for long periods of time.

Also, Turbos don't naturally fall off at high RPM, the manufacturer puts in controls to make them fall off so they don't overboost the engine. Faster engine speeds spin the turbos faster forcing more air into the engine. More air requires more fuel which makes for a bigger explosion. Really big explosions wear down that engine faster and cause heat problems. Thus, a lot of manufacturers have controls put in place to stop increasing boost after a certain RPM which is why the turbo engine feels like it falls on its face after a certain RPM.

I do agree turbos cost more money and can have a lot more issues. I don't trust too many turbo cars to be a dedicated track car. I'd rather have a straight forward and solid NA engine to beat up all day and not worry at all about it.

Funny, I noticed the huge lag every time I stomp on the pedal in my 335i compared to the M3. It might not be as bad as those cars with the large single turbos, but it's bad compared to the response of the M3. Literally night and day for anyone who can drive them both back to back.

Turbo lag is almost none existent these days and I would never own any M engine out of warranty anyway.

Speaking of out-of-warranty issues with POS engines, my N54 turbos were toast at 60k miles (need replacing) while the S54 from my old E46 M3 was still fine at 125k miles and not one issue before.

The naturally aspirated M engines have been very reliable - they are built as tough as a bank vault. S65 will be no issue out of warranty either, that I would bet on. I am leary at best about the upcoming "S55" turbo.

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A gen-u-ine BMW eff-eight-zero with them tandem clutches in the transmission and that dad gum sun roof on the top-a da cawr.

Speaking of out-of-warranty issues with POS engines, my N54 turbos were toast at 60k miles (need replacing) while the S54 from my old E46 M3 was still fine at 125k miles and not one issue before.

The naturally aspirated M engines have been very reliable - they are built as tough as a bank vault. S65 will be no issue out of warranty either, that I would bet on. I am leary at best about the upcoming "S55" turbo.

+1. BMW does know how to make an NA engine. And their M engines (and drive trains for that matter) are built to take abuse.

This. Why blame the guy when it's worldwide fuel consumption requirements (e.g. CAFE) and CO2 limits, as well as customer demand (how many "what are you MPGs" threads have we seen on here) that have driven the M brand to go with FI.

^This, it is the government that is mostly mandating all of this. I wasn't alive during the gas shortage but I imagine that it will ultimately be driven by the government standards on what we can have in the distant future until everything sorts itself out. Not to start a political thing but IMO It would also help if we got someone better in office.

I am open for change but they have to deliver at the same time, I just don't want modified stock engines in these cars that crank up the boost to put down the horsepower and torque figures. I want a car that is track ready and still can be used a practical daily driver if need be. "Street Legal Pretty Much" Change only if mandated but they cannot forget where they came from and they cannot forget the enthusiasts that made the brand what it is today. I think they are getting a little bit crazy with all these new M models I can live with the 1, and current X models but if they start to become like AMG soon we'll have something to rival the R63 it seems, let me hold back my excitement here. If they do not deliver I will definitely be switching boats to P and F cars for my fun track and weekend cars. I love these cars with a passion that I'm sure a lot of us share and it will be a sad day when they ruin what we love, hopefully this will be a change for the good.

S4's used to always be just a bit behind the M3 in performance...now they lag behind a 335. Imagine how the Audi guys feel.

Say what? Have you driven an S4? I can assure you it's not laggin behind the 335i and will in fact give the M3 a run foer it's money, in a straight line/acceleartion contest. It's quite a potent car and quit capable dynamically as well, although certainly not to the same level as the M3, specifically from a driver involvement standpoint. But it's no slouch. No Audi guy is upset over the S4, and let me tell you, that 3.0T has some impressive throttle response.

Say what? Have you driven an S4? I can assure you it's not laggin behind the 335i and will in fact give the M3 a run foer it's money, in a straight line/acceleartion contest. It's quite a potent car and quit capable dynamically as well, although certainly not to the same level as the M3, specifically from a driver involvement standpoint. But it's no slouch. No Audi guy is upset over the S4, and let me tell you, that 3.0T has some impressive throttle response.

I think M knows how to make an M engine that works for people like me. Whether they're allowed to is another story.

Give me a turbo engine with the same hp and torque curve shape as the S65 and I'll probably buy another M3. Give me an N54 turned up to 11, or something similar in concept with huge torque down low and limited upper rpm response, and I'm out. Not my bag. I love turbo engines but only if they have turbos sized to produce peak boost near redline. Last refuge of the great naturally aspirated engine might, ironically, be America. Maybe Ferd will start making hot-rod lincolns

I've thought about and posted extensively on this topic. I believe that profit is motivating BWMs switch to FI over NA for M cars much more so than government regulation. Have a look here if you are interested in my thoughts and the ensuing discussion/debate. Link.

When Kay Segler mentioned they were going to do away with the ///M dogma of high revving, high powered, small displacement NA motors, I had a sinking feeling in my gut. I really do hope they find a way around turbocharging / FI their ///M engines.

I feel it is too early to abandon a long praised theory of practice that has worked wonderfully for years. But with the demand for more efficient cars with regards to the environment, it does not look too good for our beloved ///M cars.

Big loss to lose Kay. I sat next to him at the Oktoberfest at Road America - all he could talk about was getting out on the track and doing laps. Good dude, BIG loss for M. You can't blame him that governments are requiring higher fuel economy which made it necessary to go to FI.

Big loss to lose Kay. I sat next to him at the Oktoberfest at Road America - all he could talk about was getting out on the track and doing laps. Good dude, BIG loss for M. You can't blame him that governments are requiring higher fuel economy which made it necessary to go to FI.

I don't exactly blame Kay Segler for putting FI engines in M cars. I believe it is eventually what BMW wants. M division is not independent AFAIK.

And I DO NOT buy that government/green party etc are the reason to move M engines to FI. What is the 3 series sales numbers? I believe around 800-900 thousand cars a year. What is the percentage of M3? Nothing... M3 does not have and cannot have significant effect on BMW fleets average MPG.

So they could've go to direct injection path like Ferrari did for example. Assuming that F3x M3 won't get heavier (again assuming), then they wouldn't really push the engine size above 4 liters as well. My belief is that they choose the turbo path just to cut R&D costs...